Compensator for guns



Oct. 19, 1948.. J. E. slEG comrsnsuon Fon @uns 2 Sheets-Sheet 1v Filed` Nov. 2l, 1945 FIGJ WGA

FIG.3

,o 50 allan-n FIG] Y28 FIGS I grWe/WO/b JAMES E. SIEG ci. 1943. J, E, slEG GOMPENSATOR FOR GUNS 2 Sheets-Sheet 2A lFiled Nov. 2l, 1945 JAMES E'. SIEG A Patented Got. i9, 1h48 (Granted under the lact of March 3, 1883, as amended April 30, 1928; 370 O. G. '757) 3 Claims.

This invention relates .to improvements in ordnance equipment and particularly to compensating devices for small arms.

It is well known that rapid fire or automatic weapons carried by personnel are extremely diflicul't to 'hold on the target. The rapid shocks of recoil cause the guns to swing or shift off the target. The recoil action and the noise over long periods of time are usually disturbing to the operator and affect his accuracy of fire. Even for slower re weapons, the shock of recoil and the sound of ring hinders accuracy of fire.

An important object of this invention is to provide an improved 4type of compensating device for small arms Iwhich substantially reduces the shocks of recoil and lessens the noise of firing thereby enabling ithe weapon on which it is mounted to be held steadily on the target with appreciably lessV eiort and less bodily discomfort. Ano-ther object of this invention is Ito provide a compensator for guns having these advantages without at the same time interfering with or precluding the use of standard military attachments, such as grenade launchers, bayonets and flash hiders. A further object of the invention is to provide novel control means for varying the effectiveness of the compensator and to completely cut-off the operation thereof if i-t iS so desired. A still further object of the invention is to provide a compensator of this character composed of few parts economical to manufacture and easily dismountable and attachable for inspection and cleaning. A meritorious feature of the invention is the fact that it adds little to the weight of the gun, forms an in'conspicuous and unobstructing part of the gun, and is readily adjustable .in the eld to suit 'the individuals requirements. The present invention is not only adaptable to automatic and semiautomatic rifles and similar weapons but also for slower fire ries and pistols.

Various other objects, advantages and meritorious features will become more fully apparent from the following specification, appended claims yand accompanying drawings wherein:

Fig. 1 is a View in elevation of the muzzle end of a rie incorporating -a compensating device of this invention,

Fig. 2 is a side view of a rie barrel constructed to receive the Icompensator of this' invention,

Fig. 3 is a side view, partly in section, showing the inner sleeve of 'the compensator,

Fig. 4 is a detail view of a portion of the sleeve' of Fig. 3,

Fig. 5 is an end View of the sleeve structure of Fig. 3,

`of Fig. 2, V

Fig. 7 is a top view of the sight key,

Fig. 8 is a side view of `the sight key,

Fig. 9 is a side view of the compensating device in assembled condition on a rifle barrel, partly broken away to show 'the interior arrangement of parts,

Fig. 10 is a cross sectional view along line l-I 0 of Fig. 9,

Fig. 11 is a top view of a portion of the compensator showing indicia means for indicating extent of adjustment, and

Fig. 12 is a side view of a modification of the invention, partly broken away to show the interior construction.

The compensator of this invention is adaptable to various types of guns and is herein shown applied to an automa-tic rifle. It is located at or near the forward end of the gun barrel, and one such embodiment of the invention is illustrated in Fig. l. The gun barrel is indicated at I0 and 'carries a conventional front sight l2. The compensator is generally indicated at Id. As is evident from Fig. 1, this compensator encircles the barrel immediately -to the rear of the front sightl l2. The outside diameter of the compensatoris only slightly greater than that of the barrel. Disposed immediately to the rear of the compensator is a ferrule-like member IB conically shaped to merge the outer face .of the compensator with the outer periphery -of the barrel.

The remaining figures illustrate in detail the construction of the compensator I4 and the modications made to th-e gun barrel to receive and operate the compensator. Referring to Fig. 2, the forward section of the barrel over which the compensator is received is indicated -a't I8. It is preferred, although not necessary in al1 installations,v tha-t the barrel be reduced in diameter for that Ipart of its length enclosed within .the compensator. This is the condition in Fig. 2. This reduction may be accomplished by machining the barrel `down to the desired diameter. Throughout the section I8 of the barrel a plurality of ports 20' are provided which extend from the bore 22 to the outer periphery of the section. These ports are spatially arranged longitudinally and annularly along the barrel and as illustrated extend in a forwardly inclined direction from the bore. l Preferably this inclination is at an angle `of approximately 30 to the axis of the barrel. The ports 20 are circular but because of their inclination, their mouths are elongated in a longitudinal direction as shown.

Surrounding the reduced portion I8 of the barrel is a tubular member or sleeve 24 (Fig. 3) composed of two complementary half sections as shown in Fig. 5. The sleeve is assembled on the barrel by simply bringing the two half sections together around the reduced portion of the barrel. The inside radius of the two part sleeve is such that it slidingly nts over the ported section I8. The sleeve 24 is provided with a plurality of ports 26 annularly and longitudinally spaced therearound and as shown in Fig. 3 inclined rearwardly or in the opposite direction to the ports 28 in the barrel. Preferably the ports 28 are inclined rearwardly at an angle approximately 60 to the axis of the barrel. The series of ports 25 in the sleeve correspond in number to the series of ports 20 in the barrel and the two series of ports are arranged spatially similar to one another so that in one position of the sleeve on the barrel the ports in the sleeve are brought into exact registration with the ports in the barrel. In this position, some of the gases resulting from the propelling charge pass from the bore through the forwardly inclined ports 20 in the barrel and then are caused to be reversed as they pass through the ports 26 of the sleeve.

Associated with each port 26 of the sleeve is a deflecting element against which the gases strike as they issue from the sleeve. In the present embodiment of the invention, these deflecting elements are in the form of annular iins or anges 28 forming parts of the sleeve and encircling the same in a rearwardly inclined direction. Actually, since the sleeve 24 is formed of two half sections, the flanges are similarly formed so that when the half sections are properly brought together around the barrel the flanges on one half section coextend with those on the other to form complete rings encircling the sleeve and barrel. The rearward inclination of the anges over the ports 26 causes the gases issuing from the latter to be deflected rearwardly. As shown, all the iins or flanges 28 have the same radial dimensions and in this embodiment of the invention are equally spaced apart longitudinally of the gun. The rearmost flange 38 differs from the others by being thicker as shown in Fig. 3 and having a perpendicular rear face which in assembled position abuts the front face of the ferrule I6.

The deecting ilanges 28 and the rearmost flange 30 have a radial dimension causing them to project equal distances beyond the normal peripheral surface of the barrel Ill. Adapted to overlie these flanges and enclose the sleeve 24 therein is a second tubular member or cover 32 shown in Fig. 9. This cover has an inside radial dimension such that with the front sight I2 removed it may be slipped over the muzzle of the gun and fit snugly on the flanges 28 and 35. In this position, it will hold the two halves of sleeve 24 together around the barrel. Preferably the cover has such a length that when properly assembled it extends from the rear face of the flange 30 to the rim of the foremost flange 28, leaving the balance of this flange exposed. The forward edge of the cover 32 may be beveled as shown at 34 to extend flush with the exposed portion of the leading flange 28. When fitted over the sleeve 24, the cover cooperates with the flanges 28 to sub-divide the annular space between the sleeve element and the cover element into a plurality of compartments into which the ports 26 open.

The cover 32 is provided with a plurality of openings or ports to allow for the escape of gases under pressure from the subsidiary compartments thereunder. These ports are spatially arranged in such a manner that the escaping gases counteract the tendency of the weapon to swing off the target. Firing in bursts the gun usually swings or climbs upwardly above the target and to the right. As a result, the rapid shocks of recoil cause the gun to swing about the point of contact with ones body as a fulcrum thereby causing the muzzle to swing upwardly. Similarly, the gun usually swings laterally to the right at the same time it swings upwardly but not to the same extent. This lateral swing is due to the fact that the body of the operator presents a greater resistance to the shocks of recoil on the inside of the butt toward the center of the body thereby allowing the gun to swing outwardly to the right. By permitting the gases to escape upwardly and on the right side of the compensator, these upward and lateral swinging tendencies are resisted. If the escaping gases can be proportioned to the swinging forces produced by the recoil action, it is possible to hold the gun steadily on the target through any length of firing bursts.

To provide for the escape of gases in this man-- ner, the cover element 32 is provided with a plun rality of longitudinally spaced openings or ports 36 on the top side and a plurality of longitudinally spaced ports 38 along the side toward which the gun swings laterally. The cover is otherwise closed against the escape of gases. Since the upwardly swinging tendency is greater than the lateral swinging tendency, the topside ports 3S are larger than the side ports 36 to allow for a greater. proportion of the gases collected in the compensator to escape upwardly. As shown in Fig. 10 the top side ports S are preferably in the form of transverse slots whereas the ports 38 are relatively small circular oriiices. `Both series of ports 36 and 38 communicate with each subsidiary compartment in the compensator and as shown open communication with the after end of each compartment.

The cover 32 is removably secured to the flanged sleeve 24 by the provision of a set screw 4D entering a hole 42 `at the bottom rear end of the cover and threadedly engaged at 44 in the thicker rearmost flange il@ of the sleeve, more clearly seen in Fig. 3. It is evident the set screw 4U secures the sleeve 2^. and the cover 32 jointly together with the gas escape ports of the latter arranged on the proper sides of the gun barrel to counteract the swinging tendencies thereof.

A distinctly novel feature of the invention is the provision of control means for regulating the amount of gases permitted to pass through the Compensator. This enables the operator to vary the operation of the compensator to suit his individual requirements. Not only do individuals differ from one another in the way they hold the gun and resist the recoil action, but the gun will behave differently in the diiferent ring positions. In the prone position, for example, the operator is usually able to control the swinging movement better than in the standing position ring from the shoulder or the hips. The adjusting feature of this invention enables the operator to regulate the compensator to the corm rect amount for hol-ding the gun steady on the target through short and long bursts of firing. In certain instances, such as when attachments like the grenade launcher are installed, it may be desired to completely cut off the operation of the compensator, and the regulating provision of this invention is capable of such use.

aggancia,

AfV'ari-ation l'di I'the Yoperation of fthe* compensator -is 'accomplishediby' providing ith'e sleeve Ifil-tanti its accompanying coverff3=2-` a' rotatable 'movement abcnit the 'axis-of the VJgunbarre'l. As l--previou-sly fdescribed, vthe two complementary Arhalves Aof the sleeve 24-haveianfinside :radial .fdi- -mension :such as 'to Islidingfly grip-''thelreduced rsection f'I-'8 of the 'barrel and 4theff-ports therein fare'fspatially larranged for registration with ithe -ports 20 f-in'fth'e lbarrel. Rotation 'of the fsleeve '-24 vwill vary fthe extent `of j"this 'Lreg-istration' rand :accordingly theamount of-'gasesfallowed to :escape from the bore through fthe fcompensator.' fIhe extent of this adjustment is such 'thatin one positionof-i-the sleeve, the ports 20 and 26 are in complete registration and in another position the ports 26a1'e^completlyfoutfof line with the ;portsi20. :In the former.caseithevlmaximumreffect of the compensator is obtained; inthe .latter case the sliding fit .of thesleeve 24 ,on the .gun barrel causes complete cut-off of nany 'escape of gases throughthe compensator.

The set .screw 4U hereinabove'described Aalso :has the .function .of holding -the-.compensator in Vany adjusted yposition in its rotation movement. As rshown, l.the threadedv :hole 14.4 'finto wl'iich v.the

, rset-screwvextends is open toftheeperipheryfof'the barrel fand the screwis 'flongenough Eto engage Ythe `surface of the barrel and '-.at 'the sameitime ydiunction to hold the ,cover 32cm place. It is obvious that when the set screw is backed out a little, the ported sleeve and cover are capable of joint rotation around the barrel, and that when the set screw is threaded inwardly to engage the periphery of the barrel it will hold the compensator in any adjusted position. To facilitate the holding action it is preferred that the gun barrel be indented slightly as at `45, Figs. 2 and 6 to receive the end of the set screw in fully open, fully closed and several intermediate positions of its adjustment.

To limit the adjustable movement of the compensator from a fully open position to a fully closed position and at the same time retain the gas escape ports 36 and 38 in the cover on the proper sides of the gun barrel to counteract the swinging tendency, novel provision is made at the forward end of compensator which cooperates with the key for the standard front sight l2. Referring to Figs. 1 and 9 the front sight I2 is removably held in position by a key 46, shown in detail in Figs. '7 and 8 slidingly fitted in a key way 48. The reduced section I8 of the barrel is extended far enough forward that in proper operating position of the front sight the rear end 50 of the base of the key 46 projects thereinto. This is taken advantage of to limit the rotatable movement of the compensator. On the forward end of the sleeve 24 at the base of the leading fin, an arcuate slot 52 is formed into which the rear end 50 of the front sight key extends. Upon rotation of the sleeve, the opposite ends of the slot Will be brought up against the end i! of the key thereby restricting the rotation of the sleeve to the limit of the slot. The lateral dimension of the slot is such that complete registration of the ports occurs when one end of the slot is brought up to abut the key while complete cut-off of the ports occurs when the other end of the slot is brought up against the key. In this embodiment of the invention, approximately one quarter of an inch turn is sufficient .to shift the compensator from one extreme position to the other. -Indicia means is provided for indicating the condition 6 fof the wicompensator .fin fits '.zrotative; :movement Assshownin Fig. `1'1,lthe #cover isprovidedon 'zits :rear :edge with .markings 54 A.cooperating vwith an arrnw von the zferrule :I6 'for :indicating full 'on and fulloft" positionaand :several intermediate positions.'

TIIheoperation of the'compensator is self-evifdentfrom '.thel'description hereinabove. To summarize, as each time the gunisred, azvportion of the propelling gases escape through the forrwardly :inclined sports 2li in the barrel and strike 'ftheirearwardly :inclined surfaces ofthe ports 2t andftheanges '28. YTheipressure of the gases striking against ,these lrearwardly inclined sur- -faces tend 'to iorce 1 the .gun .forward .and there- :by :reduce-.therearwardly directed shock of recoil. 'The .gases reversed fby the .deecting surfaces enter the anmilar compartments :in the comlpensator. and .thence escape from the compensatorthrough 1the=top ports v36 and the sideports i38finzthe coverV member. The vdischarge ofthe gases from the compensator in this manner Y:counteracts 'the ytendency of. the Vgun to swing upwardly and 'laterally as .previously described. VThe @ported cover not only accomplishes this ireaction but also reduces :the sound :of the ex- ;plosion 'and prevents blow-back of the gases 'toward :thecface'of the operator. Rotativo adjustment .of -the compensator will as vhereinabove @described alter Athe `effectiveness of the `compensator therebyfenabling `the *operatorl to select fthe proper proportions of the gases in the barrel for passage through the compensator to hold the gun steadily on the target. As a result, the gun will recoil with a gentle push straight to the rear whether red singly or in bursts.

A modication of the invention is illustrated in Fig. 12. A ported sleeve member 6B corresponding generally to sleeve 24 hereinabove described is provided with la series of ns or flanges S2 which are spaced unequally apart and progressively closer together from the rear end to the forward end. This modification is desirable in those instances where the heat resulting from gunfire is so unequally distributed that the rearmost flanges overheat that portion of the cover element against which they bear. By spacing the anges wider apart at this end, and progressively narrowing the spacing toward the forward end, the heat is dissipated more equally over the cover and possible overheating of any one portion thereof is nullified.

The modification also differs from the rst described embodiment of the invention by the provision on either end of the compensator 0f ferrule-like members 66 yand 68 which taperingly merge the outer face of the cover with that of the gun barrel. The forward ferrule 65 carries a bifurcated support 10, one of which is shown in th'e gure, to which a foldable front sight is removably secured, The rear face of this member is undercut to contactually receive the inclined forward end of sleeve 69. The rear member 68 is provided with a depending extension 12 having longitudinal slots 'I4-74 on its opposite sides to form a conventional connection for receiving the handle of a bayonet.

The sleeve 60 in Fig. 12 is shown as a single piece. It may be in this form or split in halves as in the case of the preceding modification of the invention. In the illustrated form in Fig. 12, the sleeve may have an internal diameter for slidingly fitting the normal size barrel or secured to the end thereof as an extension.

While I have described the preferred form of 7 my invention I do not wish to limit myself to the precise details as shown, but Wish to avail myself of such variations and modifications as may come within the scope of the appended claims.

The invention described herein may be manufactured and used by or for the government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim: t y

1. In combination with a gun barrel having a section provided with inclined means permitting gases to escape therethrough, a compensator including a sleeve encircling said section and having openings therethrough normally registering with the said inclined means, said sleeve being rotatable with respect to said section to vary the registration of Vsaid openings and inclined means, a perforated member spaced from and encircling the sleeve, and inclined members dividing the space between the sleeve and perforated member into compartments.

2. In combination with a gun barrel having a section rearward of the muzzle end provided with a plurality of longitudinally spaced and forwardly inclined ports leading from the bore to the outer periphery of the barrel, a compensator including a sleeve adjustably encircling said section and having ports therein inclined in a direction reverse to the ports in the gun barrel, said sleeve ports normally registering With the barrel ports,

8 and a perforated member encircling th'e sleeve in spaced relation thereto forming an annular chamber therebetween.

3. In combination with a gun barrel having a section rearward of the muzzle end provided with a plurality of longitudinally spaced and forwardly inclined ports, a compensator including a sleeve adjustably encircling the said section and having rearwardly inclined ports normally registering with the barrel ports, rearwardly inclined ns extending laterally of the sleeve, and a perforated member encircling and contiguous to the ns forming compartments between the ns, member and sleeve. Y

JAMES E. SIEG.

REFERENCES CITED The following references are of record in the le of this patent: f

UNITED STATES PATENTS Number Name Date 618,901 `Peterson Feb. '7, 1899 785,973 McClean Mar. 28, 1905 1,605,393 -Cutts Nov. 2, 1926 1,939,700 Hofstetter Dec. 19, 1938 2,191,484 Hughes Feb. 27, 1940/V 2,191,648 Galliot et al. Febi 27-1940 2,212,686 I-Iughes Aug. 27, 1940 2,348,114 Dow May 2, 1944 

